Jack



FIG. 1 is a rear perspective view of the jack, showing my new design;

FIG. 2 is a front perspective view of the jack;

FIG. 3 is a right side elevational view, the other side being a mirror image thereof;

FIG. 4 is a front elevational view thereof;

FIG. 5 is a rear elevational view thereof;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view of the jack illustrated in FIGS. 1-6. 

The ornamental design for a “jack”, as shown and described. 